Organ perfusion device

ABSTRACT

Disclosed is a device for the perfusion of an organ, including: a container of fluid, containing an organ bathed in the perfusion fluid; a first path including an inlet, an outlet and a pump; and a second path including an inlet, an outlet and a pump. The “arterial” outlet of the first path has a diameter smaller than a diameter of the “portal” outlet of the second path. The device additionally includes, between the pump and the outlet of the first path and/or between the pump and the outlet of the second path, an oxygenation unit arranged to oxygenate the fluid emerging from the “arterial” outlet of the first path more than the fluid emerging from the “portal” outlet of the second path. The device can include a communication path between the first path and the second path in order to oxygenate the second path. Use in liver transplantation.

TECHNICAL FIELD

The present invention relates to a device for perfusing an organ.

Such a device makes it possible for example to preserve an organ beforea transplant. The field of the invention is more particularly, butnon-limitatively, that of liver transplantation.

STATE OF THE PRIOR ART

Liver transplantation makes it possible to cure certain primary livercancers developed from cirrhosis and terminal liver diseases.Indications continue to increase. In order to increase the number ofgrafts available, it is necessary to turn to grafts having an extrarisk, and that are therefore not commonly used because there is a riskof failure which is potentially fatal for the recipient. In order toreduce this risk of failure, the conventional method is to make theperiod between the removal and the graft as short as possible. A novelmethod consists of maintaining the organ to be grafted in circulation exvivo in a perfusion medium so as to limit the harmful effects ofischemia-reperfusion. Also, in the latter case, increasing thepreservation period can make it possible to increase the number ofviability tests or even to “repair” certain livers.

The purpose of the present invention is to propose a device forperfusing an organ making it possible to:

-   -   optimize the perfusion conditions of the organ and/or increase        the preservation time of the organ, this time being able to be        used for example to produce an accurate histological and        biological evaluation; and/or    -   develop functionality tests and consequently predict the risk of        primary graft failure, and/or    -   correct metabolic anomalies, macrovesicular steatosis in        particular, by a perfusion medium and temperature, flow rate and        pressure conditions that are specifically adapted.

DISCLOSURE OF THE INVENTION

This objective is achieved with a device for perfusing an organ, saiddevice comprising:

-   -   a fluid container, arranged in order to contain an organ        immersed in a perfusion fluid,    -   a first channel comprising an inlet arranged in order to be        submerged in the container, an outlet arranged in order to be        submerged in the container, and at least one pump arranged in        order to circulate the fluid from the inlet to the outlet of the        first channel,    -   a second channel comprising an inlet arranged in order to be        submerged in the container, an outlet arranged in order to be        submerged in the container, and at least one pump arranged in        order to circulate the fluid from the inlet to the outlet of the        second channel,        the outlet of the first channel being separate from the outlet        of the second channel.

Preferably, the outlet of the first channel can have a diameter smallerthan a diameter of the outlet of the second channel.

The device according to the invention can also comprise, between thepump of the first channel and the outlet of the first channel and/orbetween the pump of the second channel and the outlet of the secondchannel, means for oxygenating the fluid, preferably arranged in orderto create a difference in the oxygenation of the fluid between theoutlet of the first channel and the outlet of the second channel.

The oxygenation means can be arranged in order to give more oxygen tothe fluid leaving the outlet of the first channel than the fluid leavingthe outlet of the second channel.

The device according to the invention preferably comprises oxygenationmeans between the pump of the first channel and the outlet of the firstchannel.

The device according to the invention may not comprise means foroxygenating the fluid on the second channel.

The pump of the first channel and/or the pump of the second channel canbe a peristaltic pump.

The device according to the invention can comprise means for regulatingthe temperature of the fluid between the pump of the second channel andthe outlet of the second channel.

The device according to the invention may not comprise means forregulating the temperature of the fluid on the first channel.

The inlet of the first channel and the inlet of the second channel canbe separate or one and the same common inlet.

The inlet of the first channel and the inlet of the second channel arepreferably one and the same common inlet.

The device according to the invention can comprise a separator betweenthe first channel and the second channel:

-   -   between the common inlet and the pump of the first channel, and    -   between the common inlet and the pump of the second channel.

The device according to the invention can comprise, between the commoninlet and the separator, a pump common to the first channel and thesecond channel.

The device according to the invention can comprise, between the commoninlet and the separator, a reservoir common to the first channel and thesecond channel.

The common reservoir is preferably placed between the common pump andthe separator.

The common reservoir can be equipped with dialysis means, preferablyarranged on a circuit parallel to the first channel and parallel to thesecond channel, the dialysis means comprising an inlet starting from thecommon reservoir and an outlet arriving in the common reservoir.

The common reservoir can be equipped with a bubble trap.

The inner diameter of the outlet of the first channel is preferably lessthan or equal to 12 mm and/or greater than or equal to 5 mm.

The inner diameter of the outlet of the second channel is preferablyless than or equal to 12 mm and/or greater than or equal to 5 mm.

The pump of the first channel and the pump of the second channel can bearranged and/or programmed so that the fluid has a flow rate at theoutlet of the second channel that is greater than a flow rate at theoutlet of the first channel.

The inlet of the first channel and/or the inlet of the second channelmay not have a cannula.

The device according to the invention can comprise means for regulatingthe temperature of the container.

The device according to the invention can comprise a first pressuresensor arranged in order to measure the pressure of the fluid in thefirst channel (preferably at less than 10 cm from the outlet of thefirst channel), between the pump of the first channel and the outlet ofthe first channel.

The device according to the invention can comprise means for controllingthe pump of the first channel so as to regulate the flow rate of thepump of the first channel as a function of pressure measurement dataprovided by the first pressure sensor.

The device according to the invention can comprise a second pressuresensor arranged in order to measure the pressure of the fluid in thesecond channel (preferably at less than 10 cm from the outlet of thesecond channel), between the pump and the second channel and the outletof the second channel.

The device according to the invention can comprise means for controllingthe pump of the second channel so as to regulate the flow rate of thepump of the second channel as a function of pressure measurement dataprovided by the second pressure sensor.

The device according to the invention can comprise a communicationchannel between the first channel and the second channel, thecommunication channel preferably starting from the first channel betweenthe oxygenation means and the outlet of the first channel. Thecommunication channel can comprise a flowmeter arranged in order tomeasure the flow rate of fluid passing through the communication channeland/or means for regulating this flow rate.

According to another aspect of the invention, a method for perfusing anorgan is proposed, implemented in a device comprising:

-   -   a fluid container, containing an organ immersed in a perfusion        fluid,    -   a first channel comprising an inlet submerged in the container,        an outlet submerged in the container, and at least one pump        circulating the fluid from the inlet to the outlet of the first        channel,    -   a second channel comprising an inlet submerged in the container,        an outlet submerged in the container, and at least one pump        circulating the fluid from the inlet to the outlet of the second        channel,        the outlet of the first channel being separate from the outlet        of the second channel.

The outlet of the first channel preferably has a diameter smaller than adiameter of the outlet of the second channel.

The method according to the invention can comprise, between the pump ofthe first channel and the outlet of the first channel and/or between thepump of the second channel and the outlet of the second channel,creating, by oxygenation means, a difference in the oxygenation of thefluid between the outlet of the first channel and the outlet of thesecond channel.

Creating the difference in the oxygenation can give more oxygen to thefluid leaving the outlet of the first channel than to the fluid leavingthe outlet of the second channel.

The method according to the invention can comprise oxygenation of thefluid between the pump of the first channel and the outlet of the firstchannel.

The method according to the invention may not comprise oxygenation ofthe fluid on the second channel.

The pump of the first channel and/or the pump of the second channel ispreferably a peristaltic pump.

The method according to the invention can comprise regulating thetemperature of the fluid between the pump of the second channel and theoutlet of the second channel.

The method according to the invention may not comprise regulating thetemperature of the fluid on the first channel.

The inlet of the first channel and the inlet of the second channel arepreferably one and the same common inlet.

The device for implementing the method according to the invention cancomprise a separator between the first channel and the second channel:

-   -   between the common inlet and the pump of the first channel, and    -   between the common inlet and the pump of the second channel.

The device for implementing the method according to the invention cancomprise, between the common inlet and the separator, a pump common tothe first channel and the second channel.

The device for implementing the method according to the invention cancomprise, between the common inlet and the separator, a reservoir commonto the first channel and the second channel.

The common reservoir can be placed between the common pump and theseparator.

The method according to the invention can comprise dialysis, by dialysismeans, of the fluid on a circuit parallel to the first channel andparallel to the second channel, the dialysis means comprising an inletstarting from the common reservoir and an outlet arriving in the commonreservoir.

The common reservoir can be equipped with a bubble trap.

The inner diameter of the outlet of the first channel can be less thanor equal to 12 mm and/or greater than or equal to 5 mm.

The inner diameter of the outlet of the second channel can be less thanor equal to 12 mm and/or greater than or equal to 5 mm.

The fluid can have a flow rate at the outlet of the second channel thatis greater than a flow rate at the outlet of the first channel.

The inlet of the first channel and/or the inlet of the second channelmay not have a cannula.

The method according to the invention can comprise regulating thetemperature of the container.

The method according to the invention can comprise measuring, by a firstpressure sensor, the pressure of the fluid in the first channel(preferably at less than 10 cm from the outlet of the first channel),between the pump of the first channel and the outlet of the firstchannel. The method according to the invention can comprise controllingthe pump of the first channel so as to regulate the flow rate of thepump of the first channel as a function of pressure measurement dataprovided by the first pressure sensor.

The method according to the invention can comprise measuring, by asecond pressure sensor, the pressure of the fluid in the second channel(preferably at less than 10 cm from the outlet of the second channel),between the pump of the second channel and the outlet of the secondchannel. The method according to the invention can comprise controllingthe pump of the second channel so as to regulate the flow rate of thepump of the second channel as a function of pressure measurement dataprovided by the second pressure sensor.

In the method according to the invention, the organ can be perfused bythe fluid which is initially at a minimum temperature comprised between0 and 10° C., before being reheated gradually by the fluid, this fluidgradually reaching a maximum temperature comprised between 33 and 43° C.

DESCRIPTION OF THE FIGURES AND EMBODIMENTS

Other advantages and features of the invention will become apparent onreading the detailed description of embodiments which are in no waylimitative, and from the following attached drawings:

FIG. 1 is a diagrammatic view of a first embodiment of the invention,which is the preferred embodiment of the invention, and

FIG. 2 illustrates different variants or modifications, each of whichcan be implemented in the first embodiment of the inventionindependently or in combination with other variants.

As this embodiment is in no way limitative, variants of the inventioncan in particular be considered comprising only a selection of thecharacteristics described or illustrated hereinafter, in isolation fromthe other characteristics described or illustrated (even if thisselection is isolated within a phrase containing these othercharacteristics), if this selection of characteristics is sufficient toconfer a technical advantage or to differentiate the invention withrespect to the state of the prior art. This selection comprises at leastone, preferably functional, characteristic without structural details,and/or with only a part of the structural details if this part alone issufficient to confer a technical advantage or to differentiate theinvention with respect to the state of the prior art.

Firstly, with reference to FIG. 1 a first embodiment of the device 1according to the invention will be described.

The device 1 is a device for perfusing an organ 2.

This organ 2, which does not form part of the device 1, is for example aliver (preferably human) intended for transplantation.

The device 1 comprises a fluid container 3, arranged in order to containthe organ (2) immersed in a perfusion fluid 4.

The fluid 4 does not form part of the device 1, but is a consumable ofthe device 1.

The container 3 is for example an open tank made from stainless steel.

The container 3 is preferably equipped with grips which make it possibleto fasten one or more additional tubes (not shown) of suitable gauge(s),each additional tube (not shown) being connected to a natural channel(example: the bile duct for the liver, the ureter for a kidney) and thecollection being carried out by gravity in a receptacle placed outsideand below the container 3.

The container 3 is for example a BackTherm container, Connectorate AG,Bernstrasse 390 CH-8953 Dietkon/Switzerland.

The perfusion fluid 4 is preferably an acellular organ preservationliquid or a buffered physiological liquid, with or without addedmolecules or cells for transporting oxygen or for a pharmacologicaleffect.

The device 1 comprises a first channel 5 comprising:

-   -   an inlet 51 arranged in order to be submerged in the container        3,    -   an outlet 52 (called arterial outlet) arranged in order to be        submerged in the container 3, and    -   at least one pump 53 arranged in order to circulate the fluid 4        from the inlet 51 to the outlet 52 of the first channel 5.

The inner diameter of the outlet 52 of the first channel 5 is less thanor equal to 12 mm (or ⅜ inch) and/or greater than or equal to 5 mm (or ⅛inch).

The different elements 51, 10, 11, 9, 53, 55, 7 of the first channel 5are preferably connected by tubes made from silicone and/or polyvinylchloride (PVC).

The inner diameter of these tubes of the first channel 5 from its inlet51 to its outlet 52 is less than or equal to 12 mm (or ⅜ inch) and/orgreater than or equal to 5 mm (or ⅛ inch).

The device 1 comprises a second channel 6 comprising:

-   -   an inlet 61 arranged in order to be submerged in the container        3,    -   an outlet 62 (called portal outlet) arranged in order to be        submerged in the container 3, and    -   at least one pump 63 arranged in order to circulate the fluid 4        from the inlet 61 to the outlet 62 of the second channel 6.

The inner diameter of the outlet 62 of the second channel 6 is less thanor equal to 12 mm (or ⅜ inch) and/or greater than or equal to 5 mm (or ⅛inch).

The different elements 61, 10, 11, 9, 63, 65, 8 of the second channel 6are preferably connected by tubes made from silicone and/or polyvinylchloride (PVC).

The inner diameter of these tubes of the second channel 6 from its inlet61 to its outlet 62 is less than or equal to 12 mm (or ⅜ inch) and/orgreater than or equal to 5 mm (or ⅛ inch).

The outlet 52 of the first channel is separate from the outlet 62 of thesecond channel.

The inlet 51 of the first channel 5 does not have a cannula. It is asimple tube end with or without a connector suitable for the diameter ofthe tube on at least one of its ends.

By cannula is meant a tube that is specifically adapted to be insertedinto an organic natural vessel or an organic natural duct.

The inlet 61 of the second channel 6 does not have a cannula. It is asimple tube end.

The outlet 52 of the first channel 5 does not have a cannula.

The outlet 62 of the second channel 6 does not have a cannula.

The arterial outlet 52 of the first channel 5 has a diameter D1 that issmaller than a diameter D2 of the portal outlet 62 of the second channel6, preferably by at least 25% i.e. (D2−D1)/D2≥25%.

The device 1 also comprises means 7 for oxygenating the fluid 4 arrangedand/or programmed and/or adjusted in order to increase the oxygen levelin the fluid 4 passing through the means 7.

The oxygenation means 7 are arranged and/or programmed and/or adjustedin order to create a difference in the oxygenation of the fluid 4between the outlet 52 of the first channel 5 and the outlet 62 of thesecond channel 6.

More specifically, the oxygenation means 7 are arranged and/orprogrammed and/or adjusted in order to give more oxygen to the fluid 4leaving the outlet 52 of the first channel 5 than to the fluid 4 leavingthe outlet 62 of the second channel 6. In other words, the oxygenationmeans 7 are arranged and/or programmed and/or adjusted so that the finaltotal concentration C1 of oxygen dissolved in the fluid 4 leaving theoutlet 52 of the first channel 5 is greater than the final totalconcentration C2 of oxygen dissolved in the fluid 4 leaving the outlet62 of the second channel 6, preferably by at least 25% or even 50% i.e.(C1−C2)/C1≥25%) or even 50%.

Thus, due to the means 7, promoting oxygenation of the arterial channel5 in comparison with the portal channel 6, the organ perfusionconditions are improved under natural physiological conditions.

The organ preservation time is improved.

The oxygenation means 7 are situated in the first channel 5. Theoxygenation means 7 are situated in the first channel 5 between the pump53 of the first channel 5 and the outlet 52 of the first channel 5.

The oxygenation means 7 are for example an oxygenator referenced DidecoD902 ECMO Phisio ND Lilliput (Mirandola, Italy). The device 1 does notcomprise oxygenation means on the second channel 6. In other words, thedevice 1 does not comprise on the second channel 6 means arranged inorder to increase, on the second channel 6, the concentration of oxygendissolved in the fluid 4.

The pump 53 of the first channel 5 is a peristaltic pump, for example acardioplegia pump of a Stokert SIII or S5 or SC (Sorin Group LivaNova)extracorporeal circulation (ECC) console or subsequent model.

Similarly, the pump 63 of the second channel 6 is a peristaltic pump,for example a cardioplegia pump of a Stokert SIII or S5 or SC (SorinGroup/LivaNova) extracorporeal circulation (ECC) console or subsequentmodel.

The device 1 comprises, in the second channel 6, means 8 for regulatingthe temperature of the fluid situated between the pump 63 of the secondchannel 6 and the outlet 62 of the second channel 6, over a range oftemperatures from at least −10° C. to +40° C., or preferably at leastbetween 4° C. and 37° C.

The temperature regulation means 8 comprise for example a heat exchangerreferenced “CSC 14 cardioplegia heat exchanger” (Sorin Group/LivaNova).

On the other hand, the device 1 does not comprise means for regulatingthe temperature of the fluid 4 on the first channel 5.

In a particularly astute manner, the structure of the device 1 is thusrationalized, manufacturing is simplified, and costs are reduced:

-   -   by only providing oxygenation means 7 on the first channel 5 in        order to create an imbalance close to natural conditions, and/or    -   by only providing temperature regulation means 8 on the second        channel 6 which has the higher flow rate.

It is noted in FIG. 1 that the inlet 51 of the first channel 5 and theinlet 61 of the second channel 6 are one and the same common inlet.

The device 1 comprises:

-   -   between the common inlet 51, 61 and the pump 53 of the first        channel 5, and    -   between the common inlet 51, 61 and the pump 63 of the second        channel 6,        a separator 9 between the first channel 5 and the second channel        6.

In other words, the first channel 5 and the second channel 6 are nottotally common and merged, but only over a portion starting from thecommon inlet 51, 61 and up to the separator 9.

The pumps 53 and 63 are separate.

The pump 53 is situated on the first channel 5 after the separator 9,but not on the second channel 6.

The pump 63 is situated on the second channel 6 after the separator 9,but not on the first channel 5.

The device 1 comprises, between the common inlet 51, 61 and theseparator 9, a pump 10 common to the first channel 5 and the secondchannel 6.

The common pump 10 is a peristaltic pump, for example a main pump of aStokert SIII or S5 or SC (Sorin Group/LivaNova) extracorporealcirculation (ECC) console or subsequent model.

The device 1 comprises, between the common inlet 51, 61 and theseparator 9, a reservoir 11 common to the first channel 5 and the secondchannel 6.

The reservoir 11 is for example a reservoir 11 referenced D 754 PH ND(Sorin Group).

The common reservoir 11 is placed between the common pump 10 and theseparator 9.

The common reservoir 11 is equipped with dialysis means 12 placed on acircuit parallel to the first channel 5 and parallel to the secondchannel 6.

The dialysis means 12 comprise an inlet starting from the commonreservoir 11 and an outlet arriving in the common reservoir 11.

The dialysis means comprise for example a Polyflux 2H artificial kidneydialyzer (Gambro/Baxter) as well as a dialysis system of the Artis type.

The common reservoir 11 is equipped with a bubble trap (not shown)arranged in order to remove bubbles of gas from the fluid 4 passingthrough the reservoir 11. The device 1 does not comprise another bubbletrap on the channels 5, 6 between the reservoir 11 and the outlets 52,62.

The pump 53 of the first channel and the pump 63 of the second channelare arranged and/or programmed (via the control means 13 describedbelow) so that the fluid 4 has a flow rate Q65 at the outlet 62 of thesecond channel that is greater than the flow rate Q55 at the outlet 52of the first channel, preferably by at least 25% i.e. (Q65−Q55)/Q65≥25%.

The device 1 is arranged and/or programmed in order to adjust (via themeans 13 described below) the flow rate of each of the pumps from thepump 53 of the first channel and the pump 63 of the second channelindependently of one another. This makes it possible to be able to actseparately on the arterial 5 and portal 6 channels in particular forfunctionality tests and/or in order to optimize the perfusion conditionsto which the organ 2 is subjected.

More specifically, the device 1 is arranged and/or programmed in orderto adjust (via the means 13 described below) the flow rate of each ofthe pumps from the pump 10, the pump 53 of the first channel and thepump 63 of the second channel independently of one another.

The device 1 comprises means 14 for regulating the temperature of thecontainer 3 (and thus regulating the temperature of the fluid 4 and/orof the organ 2 contained in the container 3), over a range oftemperatures from at least −10° C. to +40° C., or preferably of at leastbetween 4° C. and 37° C.

The means 14 typically comprise a regulator included in the electronicssystem of the BackTherm (BackTherm, Connectorate AG, Bernstrasse 390CH-8953 Dietkon/Switzerland) which bears the container 3.

The device 1 comprises a first pressure sensor 54 arranged in order tomeasure the pressure of the fluid 4 in the first channel 5 at less than10 cm from the outlet 52 of the first channel, between the pump 53 ofthe first channel 5 and the outlet 52 of the first channel 5.

The sensor 54 is for example a sensor referenced Edwards LifesciencesTruWave™ (EdisonStr. 6 85716 Unterschleissheim, Germany).

The device 1 comprises means 13 arranged and/or programmed to controlthe pump 53 of the first channel 5 so as to regulate the flow rate ofthe pump 53 of the first channel 5 as a function of pressure measurementdata provided by the first pressure sensor 54.

The device 1 comprises a second pressure sensor 64 arranged in order tomeasure the pressure of the fluid 4 in the second channel 6 at less than10 cm from the outlet 62 of the second channel, between the pump 63 ofthe second channel 6 and the outlet 62 of the second channel 6.

The sensor 64 is for example a sensor referenced Edwards LifesciencesTruWave™ (EdisonStr. 6 85716 Unterschleissheim, Germany).

The device 1 comprises means 13 arranged and/or programmed to controlthe pump 63 of the second channel 6 so as to regulate the flow rate ofthe pump 63 of the second channel 6 as a function of pressuremeasurement data provided by the second pressure sensor 64.

The means 13 only comprise technical means.

The means 13 comprise at least one computer, a central or calculationunit, an analogue electronic circuit (preferably dedicated), a digitalelectronic circuit (preferably dedicated), a microprocessor (preferablydedicated) and/or software means.

In this non-limitative embodiment example of the device 1, the means 13can for example comprise or be adapted from a control system of aStokert SIII or S5 or SC (Sorin Group/LivaNova) extracorporealcirculation (ECC) console or subsequent model.

The control means 13 are arranged and/or programmed in order to:

-   -   send a command to the pump 53, as a function of the pressure        measurement data provided by the pressure sensor 54, until the        pressure measured by the sensor 54 corresponds to or is less        than a first pressure setting (called “arterial setting”),        and/or    -   send a command to the pump 63, as a function of pressure        measurement data provided by the second pressure sensor 64,        until the pressure measured by the sensor 64 corresponds to or        is less than a second pressure setting (called “portal        setting”).

The control means comprise means for storing the first pressure setting(called “arterial setting”) and the second pressure setting (called“portal setting”), and/or means (buttons, touch screen, etc.) for inputby a user of the first pressure setting (called “arterial setting”) andthe second pressure setting (called “portal setting”).

The reservoir 11 comprises control means (not shown, but able forexample to comprise the control means 13) arranged and/or programmed inorder to:

-   -   trigger an alarm (acoustic, visual, or other) and/or stop the        pump 10 if the level of fluid 4 in the reservoir 11 exceeds a        maximum threshold, and/or    -   trigger an alarm (acoustic, visual, or other) and/or stop the        pumps 53 and 63 if the level of fluid 4 in the reservoir 11 is        less than a minimum threshold.

The device 1 also comprises a flow rate sensor 55 situated on the firstchannel 5 downstream of the pump 53 (more specifically between the pump53 and the outlet 52, more specifically between the pump 53 and themeans 7) and arranged in order to measure the flow rate Q55 of the fluid4 on the first channel 5 downstream of the pump 53 (more specificallybetween the pump 53 and the outlet 52, more specifically between thepump 53 and the means 7).

The device 1 also comprises a flow rate sensor 65 situated on the secondchannel 6 downstream of the pump 63 (more specifically between the pump63 and the outlet 62, more specifically between the pump 63 and themeans 8) and arranged in order to measure the flow rate Q65 of the fluid4 on the second channel 6 downstream of the pump 63 (more specificallybetween the pump 63 and the outlet 62, more specifically between thepump 63 and the means 8).

The device 1 also comprises a flow rate sensor 20 situated on the commonpart of the first channel 5 and the second channel 6 downstream of thepump 10 (more specifically between the pump 10 and the separator 9, morespecifically between the pump 10 and the reservoir 11) and arranged inorder to measure the flow rate Q20 of the fluid 4 on the common part ofthe first channel 5 and the second channel 6 downstream of the pump 10(more specifically between the pump 10 and the separator 9, morespecifically between the pump 10 and the reservoir 11).

Each of the flow rate sensors 20, 55, 65 is for example an externalelectromagnetic flowmeter or means of the Stokert SIII or S5 or SC(Sorin Group/LivaNova) (ECC) Console which calculates the flow rate as afunction of the rotational speed of each pump respectively 10, 53, 63and the diameter of the tubes.

The device 1 also comprises means (not shown, but able for example tocomprise the control means 13) arranged and/or programmed in order totrigger an alarm (acoustic, visual or other) and/or modify flow ratecontrols of the pumps 10, 55 and/or 65 as a function of the sign and/orof the value of:(Q55−Q65)−Q10.

This makes it possible to avoid the container 3 overflowing or emptying.

Also, the device 1 makes it possible to correct metabolic anomalies ofthe organ 2, macrovesicular steatosis in particular, by a specificallyadapted perfusion medium and temperature (via the means 8, 14), flowrate (via the sensors 55 and 65 and the means 13) and pressure (via thesensors 54 and 64 and the means 13) conditions.

A method according to the invention for perfusing the organ 2,implemented in the device 1, will now be described.

For this method:

-   -   the container 3 contains the organ 2 which is immersed in the        perfusion fluid 4,    -   the inlet 51 is submerged in the container 3, the outlet 52 is        submerged in the container 3, and the pump 53 circulates the        fluid from the inlet 51 to the outlet 52 of the first channel 5,    -   the inlet 61 is submerged in the container 3, the outlet 62 is        submerged in the container 3, and the pump 63 circulates the        fluid from the inlet 61 to the outlet 62 of the second channel        6.

The method comprises creating, by oxygenation means 7, a difference inthe oxygenation of the fluid 4 between the outlet 52 of the firstchannel 5 and the outlet 62 of the second channel 6.

In other words, the difference in the oxygenation is such that the finaltotal concentration C1 of oxygen dissolved in the fluid 4 leaving theoutlet 52 of the first channel 5 is greater than the final totalconcentration C2 of oxygen dissolved in the fluid 4 leaving the outlet62 of the second channel 6, preferably by at least 25% or even 50% i.e.(C1−C2)/C1≥25% or even 50%.

This creating a difference in the oxygenation is carried out byinjecting and dissolving oxygen in the fluid 4 (preferably only) betweenthe pump 53 of the first channel 5 and the outlet 52 of the firstchannel 5.

Creating the difference in the oxygenation gives more oxygen to thefluid 4 leaving the outlet 52 of the first channel 5 than to the fluid 4leaving the outlet 62 of the second channel 6.

The method comprises oxygenating, by the means 7, the fluid 4 betweenthe pump 53 of the first channel 5 and the outlet 52 of the firstchannel 5.

The method does not comprise oxygenating the fluid 4 on the secondchannel 6.

The method comprises regulating, by the means 8, the temperature of thefluid 4 between the pump 63 of the second channel 6 and the outlet 62 ofthe second channel 6.

The method does not comprise regulating the temperature of the fluid 4over the first channel 5.

The method comprises dialysis, by dialysis means 12, of the fluid 4 onthe circuit parallel to the first channel 5 and parallel to the secondchannel 6.

The method comprises regulating, by the means 14, the temperature of thecontainer 3 and thus of the liquid 4 and the organ 2 contained in thecontainer 3.

The method comprises controlling, by the means 13, the pump 53 of thefirst channel 5 and the pump 63 of the second channel 6 such that thefluid 4 has a flow rate Q65 at the outlet 62 of the second channel 6greater than a flow rate Q55 at the outlet 52 of the first channel 5.

During this method the fluid has a flow rate Q65 at the outlet 62 of thesecond channel that is greater than a flow rate Q55 at the outlet 52 ofthe first channel 5, preferably of at least 25% i.e. (Q65−Q55)/Q65≥25%.

The method comprises triggering an alarm (acoustic, visual or other)and/or modifying the flow rate controls of the pumps 10, 55 and/or 65 asa function of the sign and/or of the value of:(Q55−Q65)−Q10

This makes it possible to avoid the container 3 overflowing or emptying.

The method comprises measuring, by the first pressure sensor 54, thepressure of the fluid 4 in the first channel 5 (at less than 10 cm fromthe outlet 52 of the first channel 5), between the pump 53 of the firstchannel 5 and the outlet 52 of the first channel 5.

The method comprises controlling, by the means 13, the pump 53 of thefirst channel so as to regulate the flow rate Q55 of the pump 53 of thefirst channel 5 as a function of pressure measurement data provided bythe first pressure sensor 54.

The method comprises measuring, by the second pressure sensor 64, thepressure of the fluid 4 in the second channel 6 (at less than 10 cm fromthe outlet 62 of the second channel 6), between the pump 63 of thesecond channel 6 and the outlet 62 of the second channel 6.

The method comprises controlling, by the means 13, the pump 63 of thesecond channel so as to regulate the flow rate Q65 of the pump of thesecond channel 6 as a function of pressure measurement data provided bythe second pressure sensor 64.

More specifically, with regard to regulating the flow rates Q55 and Q65,the method comprises:

-   -   sending, by the means 13, a command to the pump 53, as a        function of pressure measurement data provided by the pressure        sensor 54, until the pressure measured by the sensor 54        corresponds to or is less than the first pressure setting        (called “arterial setting”), and/or    -   sending, by the means 13, a command to the pump 63, as a        function of pressure measurement data provided by the second        pressure sensor 64, until the pressure measured by the sensor 64        corresponds to or is less than the second pressure setting        (called “portal setting”).

The method comprises:

-   -   triggering an alarm (acoustic, visual, or other) and/or stopping        the pump 10 if the level of fluid 4 in the reservoir 11 exceeds        a maximum threshold, and/or    -   triggering an alarm (acoustic, visual, or other) and/or stopping        the pumps 53 and 63 if the level of fluid 4 in the reservoir 11        is less than a minimum threshold.

In this embodiment of the method according to the invention, the means 8for regulating the temperature of the fluid are used in order toregulate the temperature of the fluid over an entire range:

-   -   starting from a minimum temperature typically comprised between        0 and 10° C., preferably between 2° C. and 8° C., preferably        between 3° C. and 6° C., typically equal to 4° C.,    -   up to a maximum temperature typically comprised between 33 and        43° C., preferably between 35° C. and 41° C., preferably between        36° C. and 39° C., typically equal to 37° C.

In this embodiment of the method according to the invention, the organ 2is perfused by the fluid which is initially at the level of the means 8at the minimum temperature (typically 4° C.; in order to allow the organ2 to rebuild stores of oxygen), before being gradually reheated by thefluid, this fluid gradually reaching the maximum temperature (typically37° C.) at the level of the means 8.

This distinguishes the invention with respect to normothermic use as canbe the case for the devices of the prior art.

Of course, the invention is not limited to the examples which have justbeen described and numerous adjustments can be made to these exampleswithout exceeding the scope of the invention.

For example, non-limitatively, in variants of the device 1 which can becombined with one another and/or the method previously illustrated:

-   -   the device 1 can also comprise, in the second channel 6, between        the pump 63 of the second channel 6 and the outlet 62 of the        second channel 6, means 7 for oxygenating the fluid 4, arranged        in order to increase the level of oxygen in the fluid 4 passing        through the means 7 and/or for creating the difference in the        oxygenation of the fluid between the outlet 52 of the first        channel and the outlet 62 of the second channel, and/or    -   the device 1 can also comprise in the first channel 5, between        the pump 53 of the first channel 5 and the outlet 52 of the        first channel 5, means for regulating the temperature of the        fluid 4, and/or    -   the dialysis means 12 can be removed, and/or    -   with reference to FIG. 2 , the device 1 can also comprise, a        communication channel 72 between the first channel 5 and the        second channel 6, after the oxygenator 7 (i.e. the channel 72        starting from the first channel 5 between the oxygenation means        7 and the outlet 52 and arriving in the second channel 6        preferably between the pump 63 of the second channel 6 and the        outlet 62 of the second channel 6). Even more preferably, the        channel 72 arrives in the second channel 6 between the means 8        for regulating the temperature of the fluid and the outlet 62 of        the second channel 6. This channel 72 is arranged in order to        guide (and guides, in the embodiment of the method according to        the invention of this variant) fluid from the first channel 5 to        the second channel 6. This channel 72 is arranged in order to        oxygenate the second channel 6, so as to reduce or better        control or refine the difference in the oxygenation between the        two channels 5, 6 and thus approach the physiological conditions        of the organ 2 with even closer accuracy. A flowmeter 73 can be        connected to the channel 72, this flowmeter 73 being arranged in        order to measure the flow rate of fluid passing through the        channel 72. In addition to this flowmeter, means 74 for        regulating this flow rate (comprising for example a valve) can        be added in order to control or modify the flow rate of this        communication channel 72. The flowmeter 73 and the means 74 for        controlling the flow rate are optional, and/or    -   the pump 10 can be removed, and replaced by a gravity system,        the container 3 being placed in a raised position with respect        to the reservoir 11.

Of course, the various characteristics, forms, variants and embodimentsof the invention can be combined with one another in variouscombinations, provided that they are not incompatible or mutuallyexclusive. In particular, all the variants and embodiments describedpreviously can be combined with each other.

The invention claimed is:
 1. A device for perfusing an organ, saiddevice comprising: a fluid container, arranged in order to contain anorgan immersed in a perfusion fluid, a first channel comprising an inletarranged in order to be submerged in the container, an outlet arrangedin order to be submerged in the container, and at least one pumparranged in order to circulate the fluid from the inlet to the outlet ofthe first channel, a second channel comprising an inlet arranged inorder to be submerged in the container, an outlet arranged in order tobe submerged in the container, and at least one pump arranged in orderto circulate the fluid from the inlet to the outlet of the secondchannel, the outlet of the first channel being separate from the outletof the second channel, the outlet of the first channel having a diametersmaller than the diameter of the outlet of the second channel, thedevice further comprising, between the pump of the first channel and theoutlet of the first channel and/or between the pump of the secondchannel and the outlet of the second channel, means for oxygenating thefluid, arranged in order to create a difference in the oxygenation ofthe fluid between the outlet of the first channel and the outlet of thesecond channel, the oxygenation means being arranged in order to givemore oxygen to the fluid leaving the outlet of the first channel than tothe fluid leaving the outlet of the second channel.
 2. The deviceaccording to claim 1, further comprising oxygenation means between thepump of the first channel and the outlet of the first channel.
 3. Thedevice according to claim 1, wherein the device does not compriseoxygenation means on the second channel.
 4. The device according toclaim 1, wherein the pump of the first channel and/or the pump of thesecond channel is a peristaltic pump.
 5. The device according to claim1, further comprising means for regulating the temperature of the fluidbetween the pump of the second channel and the outlet of the secondchannel.
 6. The device according to claim 1, wherein the device does notcomprise means for regulating the temperature of the fluid on the firstchannel.
 7. The device according to claim 1, wherein the inlet of thefirst channel and the inlet of the second channel are one and the samecommon inlet.
 8. The device according to claim 7, further comprising:between the common inlet and the pump of the first channel, and betweenthe common inlet and the pump of the second channel, a separator betweenthe first channel and the second channel.
 9. The device according toclaim 8, further comprising, between the common inlet and the separator,a pump common to the first channel and the second channel.
 10. Thedevice according to claim 9, further comprising, between the commoninlet and the separator, a reservoir common to the first channel and thesecond channel.
 11. The device according to claim 10, wherein the commonreservoir is placed between the common pump and the separator.
 12. Thedevice according to claim 10, wherein the common reservoir is equippedwith dialysis means, placed on a circuit parallel to the first channeland parallel to the second channel, the dialysis means comprising aninlet leaving from the common reservoir and an outlet arriving in thecommon reservoir.
 13. The device according to claim 10, wherein thecommon reservoir is equipped with a bubble trap.
 14. The deviceaccording to claim 1, wherein the inner diameter of the outlet of thefirst channel is less than or equal to 12 mm and/or greater than orequal to 5 mm.
 15. The device according to claim 1, wherein the innerdiameter of the outlet of the second channel is less than or equal to 12mm and/or greater than or equal to 5 mm.
 16. The device according toclaim 1, wherein the pump of the first channel and the pump of thesecond channel are arranged and/or programmed so that the fluid has aflow rate at the outlet of the second channel that is greater than aflow rate at the outlet of the first channel.
 17. The device accordingto claim 1, wherein the inlet of the first channel and/or the inlet ofthe second channel does not have a cannula.
 18. The device according toclaim 1, further comprising means for regulating the temperature of thecontainer.
 19. The device according to claim 1, further comprising afirst pressure sensor arranged in order to measure the pressure of thefluid in the first channel at less than 10 cm from the outlet of thefirst channel, between the pump of the first channel and the outlet ofthe first channel.
 20. The device according to claim 19, furthercomprising means for controlling the pump of the first channel so as toregulate the flow rate of the pump of the first channel as a function ofpressure measurement data provided by the first pressure sensor.
 21. Thedevice according to claim 1, further comprising a second pressure sensorarranged in order to measure the pressure of the fluid in the secondchannel at less than 10 cm from the outlet of the second channel,between the pump of the second channel and the outlet of the secondchannel.
 22. The device according to claim 21, further comprising meansfor controlling the pump of the second channel so as to regulate theflow rate of the pump of the second channel as a function of pressuremeasurement data provided by the second pressure sensor.
 23. The deviceaccording to claim 1, further comprising a communication channel betweenthe first channel and the second channel, the communication channelstarting from the first channel between the oxygenation means and theoutlet of the first channel.
 24. The device according to claim 23,wherein the communication channel comprises a flowmeter arranged inorder to measure the flow rate of fluid passing through thecommunication channel and/or means for regulating this flow rate.
 25. Amethod for perfusing an organ, implemented in a device comprising: afluid container, containing an organ immersed in a perfusion fluid, afirst channel comprising an inlet submerged in the container, an outletsubmerged in the container, and at least one pump circulating the fluidfrom the inlet to the outlet of the first channel, a second channelcomprising an inlet submerged in the container, an outlet submerged inthe container, and at least one pump circulating the fluid from theinlet to the outlet of the second channel, the outlet of the firstchannel being separate from the outlet of the second channel, the outletof the first channel having a diameter smaller than the diameter of theoutlet of the second channel, wherein the method comprises, between thepump of the first channel and the outlet of the first channel and/orbetween the pump of the second channel and the outlet of the secondchannel, creating, by oxygenation means, a difference in the oxygenationof the fluid between the outlet of the first channel and the outlet ofthe second channel, creating the difference in the oxygenation givingmore oxygen to the fluid leaving the outlet of the first channel than tothe fluid leaving the outlet of the second channel.
 26. The methodaccording to claim 25, wherein the organ is perfused by the fluid whichis initially at a minimum temperature comprised between 0 and 10° C.,before being reheated gradually by the fluid, this fluid graduallyreaching a maximum temperature comprised between 33 and 43° C.